OBJECTIVES: This study aims to use 3D prin-ting technology based on the principle of stereo lithography apparatus (SLA) to shape dental lithium disilicate ceramics and study the effects of different slurry proportions on the microstructure and properties of heat-treated samples. METHODS: The experimental group comprised lithium disilicate ceramics manufactured through SLA 3D printing, and the control group comprised lithium disilicate ceramics (IPS e.max CAD) fabricated through commercial milling. An array of different particle sizes of lithium disilicate ceramic powder materials (nano and micron) was selected for mixing with photocurable acrylate resin. The proportion of experimental raw materials was adjusted to prepare five groups of ceramic slurries for 3D printing (Groups S1-S5) on the basis of rheological properties, stability, and other factors. Printing, debonding, and sintering were conducted on the experimental group with the optimal ratio, followed by measurements of microstructure, crystallographic information, shrinkage, and mechanical properties. RESULTS: Five groups of lithium disilicate ceramic slurries were prepared, of which two groups with high solid content (75%) (Groups S2 and S3) were selected for 3D printing. X-ray diffraction and scanning electron microscopy results showed that lithium disilicate was the main crystalline phase in Groups S2 and S3, and its microstructure was slender, uniform, and compact. The average grain sizes of Groups S2 and S3 were (559.79±84.58) nm and (388.26±61.49) nm, respectively (P<0.05). Energy spectroscopy revealed that the samples in the two groups contained a high proportion of Si and O elements. After heat treatment, the shrinkage rate of the two groups of ceramic samples was 18.00%-20.71%. Test results revealed no statistical difference in all mechanical properties between Groups S2 and S3 (P>0.05). The flexural strengths of Groups S2 and S3 were (231.79±21.71) MPa and (214.86±46.64) MPa, respectively, which were lower than that of the IPS e.max CAD group (P<0.05). The elasticity modulus of Groups S2 and S3 were (87.40±12.99) GPa and (92.87±19.76) GPa, respectively, which did not significantly differ from that of the IPS e.max CAD group (P>0.05). The Vickers hardness values of Groups S2 and S3 were (6.53±0.19) GPa and (6.25±0.12) GPa, respectively, which were higher than that of the IPS e.max CAD group (P<0.05). The fracture toughness values of Groups S2 and S3 were (1.57±0.28) MPa·m^0.5 and (1.38±0.17) MPa·m^0.5, respectively, which did not significantly differ from that of the IPS e.max CAD group (P>0.05). CONCLUSIONS The combination of lithium disilicate ceramic powders with different particle sizes can yield a slurry with high solid content (75%) and suitable viscosity and stability. The dental lithium disilicate ceramic material is successfully prepared by using 3D printing technology. The 3D-printed samples show a small shrinkage rate after heat treatment. Their microstructure conforms to the crystal phase of lithium disilicate ceramics, and their mechanical properties are close to those of milled lithium disilicate ceramics.
Printing, Three-Dimensional ; Dental Porcelain/chemistry* ; Ceramics/chemistry* ; Materials Testing ; Particle Size

Tumor cells can escape the surveillance and attack of the immune system, namely immune escape. In recent years, regulatory B (Breg) cell have attracted much attention in researches about tumor immunity. Breg cell plays an important role in tumor immune escape by secreted various cytokines. Mechanistic progress has been made in this field, which provides more targets and ideas for tumor clinical treatment. However, the phenotypic classification of Breg cells and its complex mechanism in tumor immunity still need to be systematically analyzed.

Objective: To explore the clinical characteristics, diagnosis, and treatment of ectopic thyroid gland in the parotid gland area, and to provide clinical ideas for the diagnosis and treatment of ectopic thyroid gland. Methods: A case of a normal thyroid gland with ectopic thyroid gland tissue in the parotid gland area in the neck was reported. The male patient was 20 years old. The chief complaint was the discovery of a painless mass gradually increasing under the left earlobe for one month. Clinical examination showed obvious bulging of the tissue under the left earlobe. A strip-shaped mass approximately 3.0 cm long could be palpated. It was soft in texture, with a clear boundary, and located under the skin. The skin was pale red and of normal temperature. The body position movement test was negative. Color Doppler ultrasound of the thyroid gland in the neck showed that the shape and size of the thyroid gland were normal. CT images of the head and neck showed a band-like soft tissue density shadow at the area of the parotid gland behind and below the left earlobe, with a clear boundary. The CT value was approximately 30 HU, and further enhancement yielded no additional findings. The admitting diagnosis was a mass in the left parotid gland area. The tumor was incised using a conventional surgical method for the parotid gland area. During the operation, it was found that the tumor was located under the skin, and the contents were bright-red granulomatous tissue without a capsule and adhesive to the skin tissue. The parotid gland capsule was not involved. After the tumor was completely scraped off, intermittent suturing was performed. The resected tumor was sent for pathological examination. A retrospective analysis of the diagnosis and treatment of this type of case was conducted in combination with a literature review. Results: The wound of the patient failed to heal in the first stage after the operation. By applying iodoform gauze for pressurized dressing changed weekly, the wound gradually healed about 2 months later. The postoperative pathological report showed an ectopic thyroid gland in the left parotid gland area. The results of the literature review indicate that ectopic thyroid glands can be partial or complete. In the former, normal thyroid gland tissue exists in the neck, and some thyroid gland tissue appears in other locations, mostly at the base of the tongue and mediastinum. In the latter, the thyroid gland in the neck is absent. Both can present with abnormal thyroid gland function and local compression symptoms, and the symptoms are more obvious in patients with a complete ectopic thyroid gland. Ectopic thyroid glands are mainly diagnosed and differentiated through physical examination and imaging examination. Ectopic thyroid glands occurring subcutaneously in the parotid gland area are extremely rare. Physicians should design personalized treatment plans based on clinical examinations and surgical indications. Conclusion A subcutaneous ectopic thyroid gland in the parotid gland area is rare. For ectopic thyroid gland surgery, a reasonable surgical plan should be designed considering the patient's aesthetic needs and prognosis. Puncture biopsy should be performed when necessary to formulate the surgical plan.

BACKGROUND:Metal-organic framework is an emerging porous material composed of metal nodes and organic ligands.Metal-organic frameworks can be both intrinsic photodynamic or photothermal and modified by photothermal agents or photosensitizers.Upon light irradiation,phototherapy effects are exerted through production of reactive oxygen species or rise in temperature,which is widely applied to antitumor and antibacterial treatments.When metal-organic frameworks possess both of above phototherapeutic effects,they can exert a synergistic therapeutic effect to compensate for the shortcomings of using a single phototherapy method.OBJECTIVE:To summarize recent proposed photodynamic-thermal synergistic strategies according to different structures of metal-organic frameworks,to provide new insights into the structural design,functionalization,and clinical scenarios of combined therapy metal-organic frameworks.METHODS:Using"metal-organic frameworks,photodynamic therapy,photothermal therapy"as Chinese search terms and"metal-organic frameworks,photodynamic therapy,photothermal therapy,phototherapy"as English search terms,articles were searched on PubMed,Web of Science,ScienceDirect,CNKI,and WanFang databases.Finally,76 articles were included for review.RESULTS AND CONCLUSION:(1)The combination of photothermal and photodynamic therapy has been shown to exert a synergistic effect.(2)Current strategies for combined photothermal and photodynamic therapy predominantly involve the modifying of metal-organic frameworks to impart photothermal and photodynamic properties,encapsulating phototherapeutic agents within metal-organic frameworks,forming core-shell structures with phototherapeutic agents and metal-organic frameworks,in-situ reduction of phototherapeutic agents within metal-organic frameworks,adhering phototherapeutic agents to metal-organic framework surfaces,and unique modification methods like pyrolyzing metal-organic frameworks to form metal-organic frameworks-derived carbon materials.(3)To construct metal-organic framework structures for specific phototherapy,it is essential to comprehensively consider the type,size,and binding of the phototherapeutic agents and metal-organic frameworks,and select different synthesis strategies accordingly.Encapsulation is a straightforward synthesis approach but is only suitable for small-sized phototherapeutic agents.Core-shell structures are stable,but their synthesis process is relatively complex.In situ reduction does not impose special restrictions on the size of phototherapeutic agents,but it is challenging to precisely control the growth of the phototherapeutic agents within the metal-organic frameworks.Surface attachment offers a simple synthesis step,but it cannot prevent the early aggregation and quenching of phototherapeutic agents.Surface attachment requires stringent conditions and can only be implemented with specific metal-organic frameworks.(4)The existing photothermal and photodynamic combined therapy approaches have been primarily applied in antimicrobial and antitumor treatments,demonstrating remarkable efficacy.The specific applications are related to the properties of the phototherapeutic agents and metal-organic frameworks.A minority of applications extend to rheumatoid arthritis and anticoagulation thrombolysis treatments,indicating a broad potential application scope.(5)The clinical translation of photothermal and photosensitizing agents is currently in its nascent stage,facing key challenges that include the evaluation of biocompatibility and biosafety,optimization of laser irradiation parameters,and the development of efficient methods for large-scale synthesis.

BACKGROUND:Bone marrow mesenchymal stem cells play a pivotal role in tissue engineering and bone regeneration.However,promoting the osteogenic differentiation of bone marrow mesenchymal stem cells poses a significant challenge.OBJECTIVE:To examine the influence of Fe3O4@ZIF-8 nanoparticles on the osteogenic differentiation of bone marrow mesenchymal stem cells under magnetic stimulation.METHODS:Zeolite imidazolate skeleton(ZIF-8)was synthesized by hydrothermal method,and magnetic Fe3O4@ZIF-8 nanoparticles were synthesized by one-pot method(2.5,5,10,and 20 μg Fe3O4 were added to the preparation materials,respectively).The Fe3O4@ZIF-8 nanoparticles were characterized by scanning electron microscopy,X-ray photoelectron spectroscopy,X-ray diffraction,and vibration sample magnetometer detection,and suitable materials were selected for subsequent experiments.Bone marrow mesenchymal stem cells of 4-week-old SD rats were extracted and co-cultured with Fe3O4@ZIF-8 nanoparticle solution with different mass concentrations(25,50,75,100,and 125 μg/mL),respectively.Cell proliferation was detected by CCK-8 assay,and the optimal material solution mass concentration was selected.After the mass concentration of the material solution was screened,magnetic stimulation was applied(magnetic field intensity was 0,50,100,and 150 MT,respectively).Cell proliferation was detected by CCK-8 assay,and the best magnetic field intensity and Fe3O4@ZIF-8 nanoparticles were selected for the experiment of induced differentiation of bone marrow mesenchymal stem cells.SD rat bone marrow mesenchymal stem cells were co-cultured with ZIF-8,Fe3O4@ZIF-8,and Fe3O4@ZIF-8(magnetic field intervention)nanoparticle solution,respectively.The single cultured cells were used as blank controls.Lipid induction was followed by oil red O staining.After osteogenesis induction,alkaline phosphatase,alizarin red staining and Runx2 protein concentration were detected.RESULTS AND CONCLUSION:(1)Under scanning electron microscopy,Fe3O4@ZIF-8 nanoparticles showed a dodecahedral structure.With the increase of Fe3O4 content in the material,the particle size of the nanoparticles increased.Fe3O4@ZIF-8 nanoparticles(5 and 10 μg Fe3O4 was added to the material preparation)with a particle size of about 250 nm(stable functional and biosafety of nanoparticles at this particle size)were selected.(2)The results of CCK-8 assay showed that 50 μg/mL Fe3O4@ZIF-8 nanoparticles(with 10 μg Fe3O4 added to the preparation of the material)could significantly promote the proliferation of bone marrow mesenchymal stem cells under a 100 MT magnetic field.The nanoparticles under this condition were selected for the osteogenic induction differentiation experiment of bone marrow mesenchymal stem cells.(3)After osteogenic induction,the alkaline phosphatase activity,extracellular matrix mineralization degree,and Runx2 protein mass concentration of bone marrow mesenchymal stem cells in Fe3O4@ZIF-8(magnetic field intervention)group were higher than those in other three groups(P<0.05).After adipogenic induction,the lipid droplet formation of bone marrow mesenchymal stem cells in Fe3O4@ZIF-8(magnetic field intervention)group was lower than that in the other three groups(P<0.05).(4)The results show that Fe3O4@ZIF-8 nanoparticles can promote osteogenic differentiation of bone marrow mesenchymal stem cells under specific magnetic field conditions.

In the tumor microenvironment,tumor-associated macrophages construct complex interaction networks through highly plasticity,promoting the dynamic evolution of the cancer ecosystem.With the innovation of single-cell sequencing technology,the heterogeneity,functional diversity,and interaction mechanisms of tumor-associated macrophages with tumor microenvironment have been revealed.This suggests that tumor-associated macrophages may become a new target for tumor targeted therapy,driving the development of precision anti-cancer strategies.This review summarizes the relevant research progress,explores the interaction mechanisms,describes the classification and clinical therapeutic potential,aiming to provide new perspectives and guidance for tumor research and clinical practice.

BACKGROUND:Metal-organic framework is an emerging porous material composed of metal nodes and organic ligands.Metal-organic frameworks can be both intrinsic photodynamic or photothermal and modified by photothermal agents or photosensitizers.Upon light irradiation,phototherapy effects are exerted through production of reactive oxygen species or rise in temperature,which is widely applied to antitumor and antibacterial treatments.When metal-organic frameworks possess both of above phototherapeutic effects,they can exert a synergistic therapeutic effect to compensate for the shortcomings of using a single phototherapy method.OBJECTIVE:To summarize recent proposed photodynamic-thermal synergistic strategies according to different structures of metal-organic frameworks,to provide new insights into the structural design,functionalization,and clinical scenarios of combined therapy metal-organic frameworks.METHODS:Using"metal-organic frameworks,photodynamic therapy,photothermal therapy"as Chinese search terms and"metal-organic frameworks,photodynamic therapy,photothermal therapy,phototherapy"as English search terms,articles were searched on PubMed,Web of Science,ScienceDirect,CNKI,and WanFang databases.Finally,76 articles were included for review.RESULTS AND CONCLUSION:(1)The combination of photothermal and photodynamic therapy has been shown to exert a synergistic effect.(2)Current strategies for combined photothermal and photodynamic therapy predominantly involve the modifying of metal-organic frameworks to impart photothermal and photodynamic properties,encapsulating phototherapeutic agents within metal-organic frameworks,forming core-shell structures with phototherapeutic agents and metal-organic frameworks,in-situ reduction of phototherapeutic agents within metal-organic frameworks,adhering phototherapeutic agents to metal-organic framework surfaces,and unique modification methods like pyrolyzing metal-organic frameworks to form metal-organic frameworks-derived carbon materials.(3)To construct metal-organic framework structures for specific phototherapy,it is essential to comprehensively consider the type,size,and binding of the phototherapeutic agents and metal-organic frameworks,and select different synthesis strategies accordingly.Encapsulation is a straightforward synthesis approach but is only suitable for small-sized phototherapeutic agents.Core-shell structures are stable,but their synthesis process is relatively complex.In situ reduction does not impose special restrictions on the size of phototherapeutic agents,but it is challenging to precisely control the growth of the phototherapeutic agents within the metal-organic frameworks.Surface attachment offers a simple synthesis step,but it cannot prevent the early aggregation and quenching of phototherapeutic agents.Surface attachment requires stringent conditions and can only be implemented with specific metal-organic frameworks.(4)The existing photothermal and photodynamic combined therapy approaches have been primarily applied in antimicrobial and antitumor treatments,demonstrating remarkable efficacy.The specific applications are related to the properties of the phototherapeutic agents and metal-organic frameworks.A minority of applications extend to rheumatoid arthritis and anticoagulation thrombolysis treatments,indicating a broad potential application scope.(5)The clinical translation of photothermal and photosensitizing agents is currently in its nascent stage,facing key challenges that include the evaluation of biocompatibility and biosafety,optimization of laser irradiation parameters,and the development of efficient methods for large-scale synthesis.

BACKGROUND:Bone marrow mesenchymal stem cells play a pivotal role in tissue engineering and bone regeneration.However,promoting the osteogenic differentiation of bone marrow mesenchymal stem cells poses a significant challenge.OBJECTIVE:To examine the influence of Fe3O4@ZIF-8 nanoparticles on the osteogenic differentiation of bone marrow mesenchymal stem cells under magnetic stimulation.METHODS:Zeolite imidazolate skeleton(ZIF-8)was synthesized by hydrothermal method,and magnetic Fe3O4@ZIF-8 nanoparticles were synthesized by one-pot method(2.5,5,10,and 20 μg Fe3O4 were added to the preparation materials,respectively).The Fe3O4@ZIF-8 nanoparticles were characterized by scanning electron microscopy,X-ray photoelectron spectroscopy,X-ray diffraction,and vibration sample magnetometer detection,and suitable materials were selected for subsequent experiments.Bone marrow mesenchymal stem cells of 4-week-old SD rats were extracted and co-cultured with Fe3O4@ZIF-8 nanoparticle solution with different mass concentrations(25,50,75,100,and 125 μg/mL),respectively.Cell proliferation was detected by CCK-8 assay,and the optimal material solution mass concentration was selected.After the mass concentration of the material solution was screened,magnetic stimulation was applied(magnetic field intensity was 0,50,100,and 150 MT,respectively).Cell proliferation was detected by CCK-8 assay,and the best magnetic field intensity and Fe3O4@ZIF-8 nanoparticles were selected for the experiment of induced differentiation of bone marrow mesenchymal stem cells.SD rat bone marrow mesenchymal stem cells were co-cultured with ZIF-8,Fe3O4@ZIF-8,and Fe3O4@ZIF-8(magnetic field intervention)nanoparticle solution,respectively.The single cultured cells were used as blank controls.Lipid induction was followed by oil red O staining.After osteogenesis induction,alkaline phosphatase,alizarin red staining and Runx2 protein concentration were detected.RESULTS AND CONCLUSION:(1)Under scanning electron microscopy,Fe3O4@ZIF-8 nanoparticles showed a dodecahedral structure.With the increase of Fe3O4 content in the material,the particle size of the nanoparticles increased.Fe3O4@ZIF-8 nanoparticles(5 and 10 μg Fe3O4 was added to the material preparation)with a particle size of about 250 nm(stable functional and biosafety of nanoparticles at this particle size)were selected.(2)The results of CCK-8 assay showed that 50 μg/mL Fe3O4@ZIF-8 nanoparticles(with 10 μg Fe3O4 added to the preparation of the material)could significantly promote the proliferation of bone marrow mesenchymal stem cells under a 100 MT magnetic field.The nanoparticles under this condition were selected for the osteogenic induction differentiation experiment of bone marrow mesenchymal stem cells.(3)After osteogenic induction,the alkaline phosphatase activity,extracellular matrix mineralization degree,and Runx2 protein mass concentration of bone marrow mesenchymal stem cells in Fe3O4@ZIF-8(magnetic field intervention)group were higher than those in other three groups(P<0.05).After adipogenic induction,the lipid droplet formation of bone marrow mesenchymal stem cells in Fe3O4@ZIF-8(magnetic field intervention)group was lower than that in the other three groups(P<0.05).(4)The results show that Fe3O4@ZIF-8 nanoparticles can promote osteogenic differentiation of bone marrow mesenchymal stem cells under specific magnetic field conditions.

In the tumor microenvironment,tumor-associated macrophages construct complex interaction networks through highly plasticity,promoting the dynamic evolution of the cancer ecosystem.With the innovation of single-cell sequencing technology,the heterogeneity,functional diversity,and interaction mechanisms of tumor-associated macrophages with tumor microenvironment have been revealed.This suggests that tumor-associated macrophages may become a new target for tumor targeted therapy,driving the development of precision anti-cancer strategies.This review summarizes the relevant research progress,explores the interaction mechanisms,describes the classification and clinical therapeutic potential,aiming to provide new perspectives and guidance for tumor research and clinical practice.

BACKGROUND:Magnetically responsive hydrogels have great advantages in bone tissue engineering,which is more conducive to the minimally invasive and efficient promotion of osteogenesis. OBJECTIVE:To review the application advances of magnetically responsive hydrogels in bone tissue engineering. METHODS:PubMed,Web of Science,WanFang and CNKI databases were used to search relevant literature.The English search terms were"Magnetic Hydrogels,Magnetic Nanoparticles,Superparamagnetic Nanoparticles,Fe3O4,SPIONs,Magnetic Fields,Bone Regeneration,Bone Repair,Bone Tissue Engineering".The Chinese search terms were"Magnetic Hydrogel,Magnetic Nanoparticles,Superparamagnetic Iron Oxide Nanoparticles,Magnetic Field,Iron Oxide Nanoparticles,Bone Regeneration,Bone Reconstruction,Bone Repair,Bone Tissue Engineering".After preliminary screening of all articles according to the inclusion and exclusion criteria,60 articles were finally retained for review. RESULTS AND CONCLUSION:(1)In recent years,due to the emergence of magnetic nanoparticles,more and more magnetic responsive scaffold materials have been developed.Among them,magnetic responsive hydrogels containing iron oxide nanoparticles and superparamagnetic iron oxide nanoparticles have outstanding mechanical properties and good biocompatibility.It can quickly respond to the external magnetic field and provide the magnetic-mechanical signals needed for seed cells to form bone.(2)Magnetic-responsive hydrogel can be used as a carrier to accurately regulate the release time of growth factors.(3)Under the three-dimensional microenvironment culture platform based on magnetically responsive hydrogel,the magnetic force at the interface between the magnetic response hydrogel and cells can activate cell surface sensitive receptors,enhance cell activity,and promote the integration of new bone and host bone.(4)The injectable magnetically responsive hydrogel can be used in the field of magnetic hyperthermia and biological imaging of bone tumors.(5)At present,magnetically responsive hydrogels are expected to mimic the anisotropic layered structure observed in natural bone tissue.However,most of the studies on magnetically responsive hydrogels focus on in vitro studies,and the mechanism of interaction between magnetically responsive hydrogels and the local microenvironment in vivo is still insufficient.(6)Therefore,based on the successful application of magnetic nanoparticles in magnetic resonance imaging,it is expected to optimize the properties of magnetic nanoparticles in the future to construct magnetic responsive hydrogels with suitable degradation properties,mechanical properties,and vascular functionalization,which can monitor changes in vivo in real time.